<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>天气案例</title>
    <script type="text/javascript" src="../js/vue.js"></script>
</head>
<body>
    <div id="root">
        <h2>今天天气很{{info}},{{x}}</h2>
        <button @click="changeWeather">切换天气</button>
        <!-- 
            @click="xx",xx里的内容都是在vue实例对象里面去找的，里面写alert，如果vue实例对象里没有定义alert，则直接报错 
            @xxx="yyy"  yyy可以写一些简单的语句
        -->
        <button @click="isHot = !isHot;x++">切换天气</button>
    </div>
    
</body>

<script type="text/javascript">
    Vue.config.productionTip = false // 阻止vue在启动时生成生产提示

    const vm = new Vue({
        el: '#root',
        data: {
            isHot: true,
            x:1
        },
        computed: {
            info(){
                return this.isHot ? '炎热': '凉爽'
            }
        },
        methods: {
            changeWeather(){
                this.isHot = !this.isHot;
            }
        },
    })

</script>

</html>